Abstract: The assessment of myocardial viability is of particular importance in determining the appropriate managements and making accurate prognoses in coronary artery disease patients. The new algorithms such as ²⁰¹Tl rest/redistribu-tion and nitroglycerin-augmented rest ⁹⁹Tc^m-sesbamibi and the recently performed gated SPECT, which could make a combined assessment of myocardial perfusion and LV function, have greatly enhanced the use of myocardial perfusion SPECT in the assessment of myocardial viability. The coincidence SPECT, which can perform myocardial perfusion and glucose metabolism imaging spontaneously, is nearly as powerful as PET but is less costly in the myocardial viability assessment.